Solve for $x$ and $y$ using substitution. ${-2x-3y = 3}$ ${x = -y-4}$
Answer: Since $x$ has already been solved for, substitute $-y-4$ for $x$ in the first equation. ${-2}{(-y-4)}{- 3y = 3}$ Simplify and solve for $y$ $2y+8 - 3y = 3$ $-y+8 = 3$ $-y+8{-8} = 3{-8}$ $-y = -5$ $\dfrac{-y}{{-1}} = \dfrac{-5}{{-1}}$ ${y = 5}$ Now that you know ${y = 5}$ , plug it back into $\thinspace {x = -y-4}\thinspace$ to find $x$ ${x = -}{(5)}{ - 4}$ $x = -5 - 4$ ${x = -9}$ You can also plug ${y = 5}$ into $\thinspace {-2x-3y = 3}\thinspace$ and get the same answer for $x$ : ${-2x - 3}{(5)}{= 3}$ ${x = -9}$